RCE in Coollabsio Coolify

CVE-2026-27955

Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to 4.0.0-beta.464, the executeInDocker() helper wraps commands in bash -c '{$command}' without escaping single quotes. User-controlled docker_compose_custom_build_command and docker_compose_custom_start_command fields are interpolated directly, allowing a single quote to break out of the bash -c argument and execute commands on the managed server host (outside the intended Docker container context). This vulnerability is fixed in 4.0.0-beta.464.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.004 (31.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-27955: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-27955?
CVE-2026-27955 is a medium-severity vulnerability in Coollabsio Coolify, classified under OS Command Injection. CVSS score: 6.6/10. Published 2026-06-30.
How severe is CVE-2026-27955?
Medium severity. CVSS v3 base score is 6.6 out of 10.